The invention relates to an electronic device, in particular, to a flat panel display device named field ion display (FID). It can be used as a color or a black-white display of television or computer, and also can be used as a display for pictures and characters in other situations.
At present, information technology is developing fast worldwide. As a window to exchange information between human and machine, display device plays a very important role in it. Up to now, cathode ray tube (CRT) can produce the highest quality image among all kings of display devices. However, CRT has the disadvantages of huge bulk and having to be paneled. The present flat panel displays, such as the liquid crystal display (LCD), the plasma display panel (PDP), the field emission display (FED), etc., due to their problems in principles and technologies, have the following common shortcomings: the image quality is not satisfactory and is not easy to produce. So the cost performance ratio is lower than that of CRT. For example, LCD can be used as a display device by using electric signal to change the arrangement of the molecules of the liquid crystal, to moderate the external light. Japan has developed the LCD to a considerable degree, occupying 99% of LCD market, but in many performance levels, LCD is lower than that of CRT. Moreover, the voltage and power consumption of a color LCD are not as low as indicated, because it needs a back light source when operating. PDP, as another example, produces ultraviolet ray by use of gaseous glow discharge, thereby stimulating the color fluorescent materials. As the light of gaseous glow discharge influences the color purity of fluorescent materials, and the pixels cannot be fabricated small enough to guarantee sufficient brightness, it is not possible to get the same color fidelity and resolution for PDP as that of CRT. Now most PDP is made as large screen TV with an area of about 1 square meter. As the cost performance ratio is lower than that of CRT, its prospect is not optimistic. As the most advanced flat panel display device, FED adopts the flat panel cold field emission tips array instead of the thermal emission electronic gun. It is the best scheme to turn CRT into a flat panel display, but to fabricate the tips array in homogeneous field emission distribution on a large area is very difficult, and the energy of electronic beam is too low, which can only stimulate the low voltage fluorescent materials instead of the high voltage ones. Therefore, the color fidelity of FED cannot reach the level of CRT. Although large amount of financial support and technological forces have been gathered to develop FED, its high cost and low quality of color image still prevent it from entering the market.
To overcome the above shortcomings of the above flat panel display, the invention provides a flat panel display named field ion display FID, which can provide good quality image, with low cost and energy consumption.
To achieve the object of the invention, there is provided a field ion display device FID, which comprises: a fluorescent plate 3, a field ion emission plate 1 and a microchannel plate 2, the field ion emission plate 1, the microchannel plate 2 and the fluorescent plate 3 are arranged parallel to each other, with gaps there between and microchannel plate 2 arranged between the other two plates, and being peripherally sealed with a thin gas filled inside, wherein an X-line electrode system 4 is provided on the inner side of the field emission plate 1, each X-line electrode including a plurality of fine wedge shape lines connected parallel; a Y-line electrode system 5 is provided on the side of the microchannel plate 2 facing the field ion emission plate 1, an accelerating electrode 6 is provided on the other side of the micro-channel plate 2, each crossing point of the Y-line electrodes 5 on the micro-channel plate 2 and the X-line electrodes 4 on the field ion emission plate 1, is an addressing point of X-Y encoding. On those addressing points there are many microchannel holes 8 passing through the microchannel plate 2; On the inner side of the fluorescent plate, facing every addressing point high voltage fluorescent pixels 9 are provided, on which a thin aluminum film is deposited as a screen electrode 7.
Preferably, the substrates of the field ion emission plate 1 and microchannel plate 2 are made of insulating material, and the fluorescent plate 3 is made of transparent insulating material.
Preferably, the X-line and Y-line electrode systems 4 and 5 are addressed by X-Y encoding. The lead wires of the X-Y electrode systems, the accelerating electrode 6 and the screen electrode 7 are all left outside of the sealed field ion display to be connected with the driving circuits of the FID.
Preferably, the field ion display device is filled with thin gas (10xe2x88x92414 10xe2x88x925 tor).
To achieve the object of the invention, there is also provided a method for producing the field ion display device FID, the FID comprises a fluorescent plate 3, a field ion emission plate 1 and a microchannel plate 2, the method comprises the steps of: providing the X-line electrode system 4 on the inner side of the field ion emission plate 1, each X-line electrode is formed by many very fine wedge shape lines; providing the Y-line electrode system 5 one the side of the surface of the microchannel plate 2 facing the field ion emission plate 1; providing the accelerating electrode 6 on the other side of the microchannel plate 2, each crossing point of the Y-line electrode on the microchannel plate 2 and the X-line electrode on the field ion emission plate 1 is an addressing point, on those addressing points on the microchannel plate 2 there are many microchannel holes 8 passing through; providing, on the inner side of the fluorescent plate facing to the addressing points, the phosphorous pixels 9, which are alternated in order with three original colors, i.e. red, green and blue, on which a thin aluminum film is deposited as screen electrode 7, arranging the field ion emission plate 1, the microchannel plate 2 and the fluorescent plate 3 parallel to each other with gaps there between, the microchannel plate 2 being arranged between the other two plates, and sealing the above three plates peripherally with a thin inert gas filled inside (10xe2x88x92414 10xe2x88x925 tor). The X-line electrode system 4 and Y-line electrode system 5 are addressed by X-Y encoding.
Preferably, the field ion emission plate 1 and the microchannel plate 2 are made of insulating material and the fluorescent plate 3 of transparent insulating material.
The operation mechanism of FID:
As a signal voltage is applied to an addressing point (Xi,Yj), the positive field ions are emitted from the corresponding point on the field ion emission plate 3 based on the signal strength, then pass through the microchannel holes 8, impinge on the wall of the holes, so that the multifold secondary electron emissions are multiplied. The secondary electrons are accelerated by the accelerating electrode 6, converting into a strong electron flow, then are extracted from the other side of the holes, being accelerated again by the screen electrode 7, and finally bombard a corresponding pixel on the fluorescent plate 3, thereby stimulating the fluorescent light to produce an image.
The advantages of FID:
(1)Field ion emission is easier to realize than the field electron emission, so FID is easier to produce than FED. Furthermore, FID is cheaper to manufacture than FED, the cost of FID is of the same level as that of CRT.
(2)The microchannel plate of FID converts the ion emission beam into a high electron beam and stimulates the high-voltage fluorescent material, and also it can divide the colors of the signal just as the shielding plate does in CRT. Therefore, the color image quality can reach the level of CRT. Furthermore, the structure of FID is relatively simple and its cost is considerably low.
(3)FID makes use of the field ion cold emission and works in the self-exited dark discharge region of the gas, all of the energy consumed being used for accelerating the ions and electrons, so the efficiency of FID can reach the level of LCD.
(4)FID realizes very high image resolution, with 100 pixels per square mm. Therefore, FID can reach the level of FED.
(5)Increasing the diameter of the microchannel holes and the thickness of the microchannel plate, we can get a large area microchannel plate. Therefore, it is quite easy to realize a large screen display.